Stamp pads



Nov. 21, 1961 H. F. KENT 3,009,440

STAMP PADS Filed June 10, 1958 INV EN TOR.

United States Pate t 3,009,440 STAMP PADS Hans F. Kent, Cliifside Park, NJ. Filed June 10, 1958, Ser. No. 741,152 3 Claims. (Cl. 118-264) This invention relates to stamp or inking pads, and its primary object is to provide a pad subdivided into sections, each of which sections may carry an ink of a different color, so that a stamp inked thereon may impress its different parts and characters in different colors. The invention applies also to so-called self-inking stamps which, though being used for stamping, show the characteristics of stamp pads, too. A further field of application are marking and stamping devices or machines and printing processes that are based on superimposing printing characters onto predetermined inking areas, be it in straight or rotary motion.

While multicolor stamping was up to now intricate, costly, and yet limited, the method incorporated in this invention provides multicolor inking pads at modest costs, applicable not only to straight lines but also to curves, such as used in heraldics and advertising.

The drawings illustrate the invention, and in these:

FIGURE 1 is a fragmentary perspective view of a stamp pad constructed in accordance with the invention;

FIGURE 2 is a similar view of a modification;

FIGURE 3 shows another modification.

Referring now to the drawings for a detailed description, and at first to FIGURE 1, the numeral 1 designates the pad generally. The pad is an integral or single body of either sponge rubber or of resilient sponge of synthetic resinous plastic, and may be an integral body of such material separated into sections 11, 11 11 11 and 11 by resilient, non-porous or ink-impervious walls or partitions 13 extending from top to bottom of said body and formed by impregnating the sponge body with a liquid or semiliquid substance, such as plastic rubber, latex or synthetic plastic compounds or an adhesive, all of which become finally solid though resilient or elastic on drying.

The different sections of the pad may be inked with inks of selected colors, so that a stamp pressed onto the pad may receive and print characters in the various colors, the mentioned non-porous walls or partitions serving to prevent the differently colored inks from leaking or migrating into adjoining sections.

FIGURE 1 shows the tops of the partitions as being concave, the purpose being to further guard against any slight possible creepage of ink at the surface of the pad from one section to another, the concavities functioning to collect an ink which may seep out of its section, in which concavities or channels such ink will dry. The

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walls of these channels are made ink-impervious by being coated with one of the ink-impervious substances mentioned above. The channels are usually formed at the top of the partitions, but may appear, in addition, also at the bottom, both types designated 12 in FIGURE 1. As the rule, such channels originate from pressing the ink-impervious substances into the sponge body. During the process of drying, said substances become more and more sticky. Consequently, the sponge body, penetrated by these substances, can be formed by being subjected to pressure, and it finally settles in the intended shape and in a state of compression that causes the channel like structures. However, if complete penetration of the sponge body by the mentioned substances can not become achieved-as is the case when the sponge pad is too thick or its material too firm-shallow artificial channels may be cut into the surface of the pad, and the process of forming partitions may start from the bottom of the precut channels towards the bottom of the pad.

FIGURE 2 shows a structure similar to that of FIG- URE 1, except that the tops of the walls or partitions are convex, and for the purpose of keeping the differently colored inks within their respective sections, the latter being designated 16, 16 16 16 and 16 the body 14, the partitions 15, and the bottom channels 17.

FIGURE 3 is also similar to FIGURE 1, except that the sponge 18 has a circular partition 19 and a right angular partition 20, both of which are concave at top and bottom. It demonstrates that the principles embodied in this invention permit color separation of every shape, even in curved designs.

What is claimed is:

1. A stamp pad comprising an integral body of resilient sponge material impregnated with ink-impervious resilient material so as to form impervious, resilient, vertical partitions subdividing said body into sections.

2. The stamp pad specified in claim 1, in which there are channels at the upper and lower surfaces of said partitions.

3. The stamp pad specified in claim 1, in which there are ridges of ink-impervious resilient material at the upper and lower surfaces of said partitions.

References Cited in the file of this patent UNITED STATES PATENTS 379,793 Laughton Mar. 20, 1888 1,421,952 Kee et al July 4, 1922 2,117,470 Zareko 'May 17, 1968 2,392,521 Chollar Jan. 8, 1946 FOREIGN PATENTS 4,940 Great Britain Mar. 4, 1896 

